P38A ABS pump stopped

Hi All,
My ABS pump has stopped running at all and brake pressure is obviously low. Checked and swapped the abs relay and checked the 40a fuse but still nothing. Looking at possibly pressure switch or motor brushes. Any ideas on a diagnostic process to go further before we start spending..big.!

Bagshot said:

Hi All,
My ABS pump has stopped running at all and brake pressure is obviously low. Checked and swapped the abs relay and checked the 40a fuse but still nothing. Looking at possibly pressure switch or motor brushes. Any ideas on a diagnostic process to go further before we start spending..big.!

Click to expand...

You can check the pressure switch continuity with an ohm meter, likewise you can do a basic check on the motor for continuity. You can also check for power at the motor connector. Don't discount a possible problem with the fuse box.

Datatek said:

You can check the pressure switch continuity with an ohm meter, likewise you can do a basic check on the motor for continuity. You can also check for power at the motor connector. Don't discount a possible problem with the fuse box.

Click to expand...

Cheers,
Multi meter coming out and going to check underside of fuse box. Heard that they can perish or corrode on the solder joints..?

They do often burn-up as joints go HR and generate even more heat as they try to pass high-amps.
I changed one out as a problem diagnosis step on the last Rangie and it made no difference to my problem.
So I have a complete unit with all fuses and relays to use as spares, as and when.
What shall we all do when the supply of units completely dries up I wonder?

DanClarke said:

They do often burn-up as joints go HR and generate even more heat as they try to pass high-amps.
I changed one out as a problem diagnosis step on the last Rangie and it made no difference to my problem.
So I have a complete unit with all fuses and relays to use as spares, as and when.
What shall we all do when the supply of units completely dries up I wonder?

Click to expand...

Got the fuse box out and taken all fuses and relays off,( photo taken) first cover off but can't get the circuit board out to check underneath..offers of advice. ?!

Bagshot said:

Got the fuse box out and taken all fuses and relays off,( photo taken) first cover off but can't get the circuit board out to check underneath..offers of advice. ?!

Click to expand...

All looks clean and no burnt smells so far.

Might be in here?

Datatek said:

You can check the pressure switch continuity with an ohm meter, likewise you can do a basic check on the motor for continuity. You can also check for power at the motor connector. Don't discount a possible problem with the fuse box.

Click to expand...

Hi @Datatek
Gone to the extent of taking off the motor body from the pump, (everything else seems ok). Am I right in thinking with no measurement across either the plug contacts or the wires entering into the motor, we have a problem.
Also connected 12v direct to the connectors and nothing..?

Bagshot said:

Hi @Datatek
Gone to the extent of taking off the motor body from the pump, (everything else seems ok). Am I right in thinking with no measurement across either the plug contacts or the wires entering into the motor, we have a problem.
Also connected 12v direct to the connectors and nothing..?

Click to expand...

If you apply volts direct to the motor (the big connector with 2 wires) then it's likely the brushes are worn out, however if you have no volts from the wire end of the connector with the ignition on, there is clearly another problem.

Hi @Datatek, thanks for your help..
Well problem found and new one to sort..
No continuity through the motor, leads to contacts ok, so put 12v straight to the contacts and nothing moving. Conclude that brushes are shot, so as it's probably as it's a new (more likely S/H) pump, might as well dig in to it. After a bit of effort as the back plate is crimped on, got to the brushes and yes all worn away and plastic carrier's melted,(see below brush and carrier on LH side). Must have been struggling for some time.

Looking around these brushes aren't available anywhere, never mind the carriers. So now my second problem trying to find a decent pump that doesn't cost a whole car..

Update.
Planning to remake the brushes, not as difficult as first thought if I can get the old blocks out of the holders.

got a new to me pump from emmotts of colne couple years ago £50. Worth a look on there website emmottsofcolne.co.uk.
Hth

Cut bigger ones that are available down to size maybe?
You could solder them the other way rouñd for now, will work until you get parts and help identify if that is the only issue. Gave a 3rd life to my starter, still going strong and brushes were worse than that.

Complete failure..!!!
Managed to get old brushes out, made new ones fit and reassembled... Three times..!!!.
Dead.
Continuity through to the brushes, everything in place but no movement when assembled. So ditching it, second hand unit on order. (Worth a go..)
Boll####.!!!

Always worth a try. Brushes weren’t expensive are still new and at least you know itl be decent one with your new brakes